(a) Field of the Invention
The present invention relates to a liquid crystal display, and more particularly, to a liquid crystal display having pairs of power source supply lines and a method for forming the same.
(b) Discussion of the Related Art
A liquid crystal display (hereinafter referred to as an LCD) is one of the most widely used flat panel displays. The LCD includes two display panels provided with electric field generating electrodes, such as a pixel electrode and a common electrode. A liquid crystal layer is interposed between the two display panels. In the LCD, voltages are applied to the electric field generating electrodes to generate an electric field in the liquid crystal layer. Due to the generated electric field, liquid crystal molecules of the liquid crystal layer are aligned and polarization of incident light is controlled, thereby displaying images.
The LCD also includes switching elements connected to the respective pixel electrodes, and a plurality of signal lines such as gate lines and data lines for controlling the switching elements and applying voltages to the pixel electrodes.
The liquid crystal display receives an input image signal from an external graphics controller. The input image signal contains luminance information of each pixel PX of the LCD. The luminance information represents a given gray level. Each pixel is applied with the data voltage corresponding to the desired luminance information. The data voltage applied to the pixel is a pixel voltage that represents a difference between a reference voltage, such as a common voltage, and an image signal. Each pixel displays luminance representing a gray level of the image signal according to the pixel voltage. Here, the range of the pixel voltage that is capable of being used by the liquid crystal display is determined according to a driver.
The driver of the liquid crystal display is mounted on the display panel in a form of a plurality of IC chips, or is installed on a flexible circuit film and attached to the display panel. The cost of manufacturing the IC chip represents a high portion of the total manufacturing cost of the liquid crystal display. Particularly, the cost of manufacturing the driver of the liquid crystal display is increased as the number of data lines applying the data voltage is increased.
Also, to provide for adequate display quality of the liquid crystal display, should have a high contrast ratio, excellent viewing angle, and fast response speed.